Split Zoom preference to 3D View zoom and Timeline Zoom

In the 3D view, one important navigation feature for many users is the ability to choose the direction of the zoom. Indeed, some prefer to zoom in by dragging the mouse toward the top of the viewport, and some prefer to zoom out for this same action. Good thing is that there is the Invert Zoom Direction setting in the Preference->Navigation->Zoom to configure that as we wish.

The issue though is that when we change this setting, it also invert the direction of the zoom in the Timeline panel, on the time ruler. That affect both the Mouse and the Wheel checkboxes. And that's an issue, especially when we use a tablet, because we can have a preferred direction for the 3D view that is different from the one we use to zoom in the time range.

The request here is then to split the zoom settings in 2 parts, one for the 3D view, quite similar to what we have at the moment, and one for the time. This not only makes sense because these are unrelated dimensions, but also because we usually tend to zoom vertically in the viewport and horizontally in the timeline.

So my suggestions to fix this, and to allow users to control both kinds of zooms independently (in my case to invert the direction in the viewport without changing the direction in the Timeline panel) are these:

• The current Zoom section should be named "3D View Zoom" and can stay the same as it is now, except that none of its settings should affect the timeline zoom.

• A new Time Zoom section should be introduced in this Navigation tab. It could contain the same settings, but the most important ones are the 2 Invert Zoom directions. It would also be really really nice if a Zoom To Mouse Position would be added, to allow the time zoom to be done right under the mouse instead of the middle of the time range.

• Another nice setting that could also be added is a setting to control the sensitivity of the zoom when we use the mouse, because at the moment it is not that easy to zoom in just a little.